1. Field of the Invention
The present invention relates generally to a washing machine, and more particularly, to a disinfecting washing machine equipped with a disinfecting liquid dispenser.
2. Description of the Related Art
Colloidal silver can be produced by forming silver ions (Ag+) and dissolving them in water. The colloidal silver is used as an antibacterial agent or a bactericide. It is reported that the colloidal silver eliminates about 650 different kinds of bacteria. In particular, the colloidal silver is characterized as not inducing resistance, which is different from general antibiotics, and is safe because the colloidal silver has no toxic effects. Methods of manufacturing the colloidal silver are an electrolysis method, a chemical resolution method and a pulverization method.
A disinfecting washing machine is a washing machine that is equipped with a disinfecting liquid dispenser that produces and supplies a colloidal silver to disinfect laundry through antibacterial and bactericidal actions of the colloidal silver.
A conventional disinfecting washing machine is described below with reference to FIGS. 1 and 2.
FIG. 1 is a cross section of a conventional disinfecting washing machine. As shown in FIG. 1, a water tub 104 is disposed in a body casing 102 to contain washing water. A washing tub 106 is disposed in the water tub 104. A pulsator 108 is mounted in a lower portion of an interior of the washing tub 106 to be rotated in forward and reverse directions so as to form currents of the washing water. A drive unit 110 is positioned under the water tub 104 to rotate the washing tub 106 and the pulsator 108. The drive unit 110 comprises a drive motor 112 and a power transmission unit 114. The drive motor 112 is rotated by power supplied thereto, and the power transmission device 114 serves to selectively transmit power generated by the drive motor to the pulsator 108 and the washing tub 106. A belt 116 is wound around the drive motor 112 and the power transmission device 114 to mediate transmission of the power. A drain assembly 118 comprises a pipe 118a to drain the washing water from the washing tub 106 and a drain pipe valve 118b, which selectively opens and closes the drain pipe 118a to allow draining of the washing water from the washing tub 106.
FIG. 2 is a partially sectional view of a conventional disinfecting liquid dispenser. As depicted in FIG. 2, when power is supplied to the washing machine and a washing course is selected while laundry is contained in a disinfecting washing machine, washing water is fed into an interior of a water tub 104. The washing water fed into the water tub 104 dissolves a detergent while passing through a detergent dispenser (not shown), and is supplied to the water tub 104 along with the dissolved detergent.
If a user selects a disinfection washing course, an inlet valve 204 of a disinfecting liquid dispenser 120, connected to external source of water through an inlet pipe 212, is opened and the water is supplied to an interior of a storage container 122, whereas the washing water is fed to the water tub 104. When power is applied to two silver plates 220 and 222 of the disinfecting liquid dispenser 120, a silver disinfecting liquid is produced. The silver disinfecting liquid is supplied to the interior of the washing tub 106 and disinfects the laundry.
The water supplied though an inlet 202 of the storage container 122 is halted to stabilize a speed and a current of the water while filling a first space 210 of the storage container 122. The water contained in the first space 210 overflows a first partition 206 and flows into a second space 214. The water having passed through the first space 210 and flowing into the second space 214 fills the second space 214 to a water level corresponding to the height of a second partition 208. After the second space 214 is filled with the water, the water overflows the second partition 208 and flows into a third space 224 and then is supplied to the interior of the washing tub 106 through an outlet pipe 124 from an outlet 216 of the storage container 122. The water flows into the third space 224 while a certain amount of the water is contained in the second space 214. In a process, the silver disinfecting liquid is produced through electrolysis in the water, and the produced disinfecting liquid is supplied to the washing tub 106 through the outlet 216. The process of producing a disinfecting liquid is continuously carried out while the water is supplied to the storage container 122. A top 218 of the storage container 122 fixedly holds the sliver plates 220 and 222 in the water contained in the second space 214. The storage container 122, the top 218, the inlet 202, the outlet 216 and the bypass pipe 128 may be of a nonconductive material.
Further, in the process of producing the disinfecting liquid, if the amount of the water supplied through the inlet 202 is large, the water contained in the interior of the storage container 122 flows into a drain pipe 118a through a bypass pipe 128 from a bypass outlet 126 at an upper portion of the storage container 122, so the water can be maintained at an appropriate water level in the storage container 122, thereby enabling a disinfecting liquid of a certain concentration to be produced. When the process of producing a disinfecting liquid is stopped, the water supply to the storage container 122 is stopped by closing of the inlet value 204 and the power to the silver plates 220 and 222 is stopped. At that time, the water remaining in the interior of the storage container 122 flows into the outlet 216 through remaining water discharging holes 206a and 208a and is completely discharged from the storage container 122.
After the washing water including the disinfecting liquid fills the washing tub 106, washing of the laundry is performed by a rotation of the pulsator 108 and bacteria are killed by the disinfecting liquid in a process of the washing of the laundry.
The disinfecting liquid dispenser 120 carries out the electrolysis in the water by alternately applying a positive voltage and a negative voltage to the two silver plates 220 and 222, respectively, thus generating the silver ions. The amount of the silver ions, which is a concentration of the colloidal silver, is proportional to an amount of current flowing through the two silver plates 220 and 222 or an amount of voltage applied to the two silver plates 220 and 222.
The disinfecting performance obtained by the colloidal silver is determined by the concentration of the colloidal silver. If the concentration of the colloidal silver is excessively low, a disinfecting performance of the colloidal silver decreases; but if the concentration of the colloidal silver is excessively high, the colloidal silver discolors the laundry. Accordingly, the concentration of the colloidal silver has to be appropriately adjusted so as not to damage the laundry while disinfecting the laundry. To produce the appropriate concentration of the colloidal silver, the amount of voltage applied to the two silver plates 220 and 222 or the amount of current flowing through the two silver plates 220 and 222 has to be appropriately adjusted.
Since the concentration of the colloidal silver is varied according to a pressure and temperature of the water, the voltage applied to the two silver plates 220 and 222 or the current flowing through the two silver plates 220 and 222 must not be limited to a fixed value but must be varied in a certain range so as to maintain the concentration of colloidal silver in an appropriate range.